Papers
Read the series in order
Each paper solves a different failure of founder reasoning: naive cooperation analysis, naive departure narratives, and naive cofounder selection.
Repeated Games and the Cofounder Problem: Why Startup Cooperation Depends on Shared Time Horizons
Cooperation survives only when founders share a long enough time horizon.
cooperation constraint
delta >= (T - R) / (T - P)
A startup is not a one-shot negotiation. It is a repeated game played through hiring, product crises, financing pressure, and daily trust updates. This paper applies repeated-game theory to cofounder relationships and shows why long-term cooperation depends less on abstract loyalty than on shared time horizons, sufficiently high discount factors, and freedom from external games that dominate short-term decisions.
繰り返しゲームとしての共同創業者関係: スタートアップ協力はなぜ時間軸の共有に依存するのか
Cooperation survives only when founders share a long enough time horizon.
cooperation constraint
delta >= (T - R) / (T - P)
スタートアップは1回限りの交渉ではない。採用、開発、資金調達、危機対応、責任分担を通じて、同じプレイヤーが何度も協力と非協力を選び続ける繰り返しゲームである。本稿は共同創業者関係を repeated game として定式化し、協力が持続する条件と、能力があっても関係が壊れる構造的理由を説明する。
Founder Exit Threshold Model: Why Cofounders Rarely Leave Gradually
Departure is a regime shift caused by accumulated pressure, not a mood change.
exit hazard
X_t >= tau_i for H rounds
Founder departures are often narrated as emotional drift, but they behave more like threshold events. This paper models cofounder exit as a nonlinear transition: multiple stress variables accumulate over time, and once a founder's exit pressure crosses a personal threshold for long enough, the organization moves from unstable cooperation into departure dynamics.
創業者離脱の閾値モデル: 共同創業者はなぜ徐々にではなく相転移的に離脱するのか
Departure is a regime shift caused by accumulated pressure, not a mood change.
exit hazard
X_t >= tau_i for H rounds
共同創業者の離脱は、気分の低下や関係悪化として物語られがちだが、実際には複数の状態変数が積み上がり、ある閾値を超えた時に非線形に起こることが多い。本稿は founder exit を threshold crossing として定式化し、離脱がどのように準備され、なぜ直前まで見えにくいのかを説明する。
Cofounder Matching Fit Function Model: How to Evaluate Who Should Build Together
The right founding pair is chosen by structural fit, not charisma or convenience.
pair selection
F_ij = rewards - penalties
Most founders select partners through intuition, chemistry, or convenience. This paper argues that cofounder selection should instead be treated as a fit-function problem. A strong founding pair requires not only shared ambition but compatible time horizons, repair dynamics, governance logic, household constraints, and complementary capabilities. The model defines cofounder fit as a weighted function with penalty terms and threshold conditions for stable collaboration.
共同創業者マッチングの適合関数モデル: 誰と組むべきかをどう評価するか
The right founding pair is chosen by structural fit, not charisma or convenience.
pair selection
F_ij = rewards - penalties
共同創業者選定は、直感、相性、勢いで行われがちだが、それではコストが高すぎる。本稿は cofounder selection を fit-function problem として捉え、ミッション整合、時間軸整合、能力補完、ガバナンス適合、修復可能性、外部ゲーム制約などの変数から、誰と会社を作るべきかを定量的に考える枠組みを提示する。